Portable speaker



FIG. 1 shows a front perspective view of the portable speaker;

FIG. 2 shows a front view of the portable speaker;

FIG. 3 shows a rear view of the portable speaker;

FIG. 4 shows a first side view of the portable speaker;

FIG. 5 shows a top view of the portable speaker; and,

FIG. 6 shows a bottom view of the portable speaker.

The portions of the graphical user interface shown in broken lines form no part of the claimed design. 

CLAIM I claim the ornamental design for a portable speaker, as shown and described. 